Steam trap



Dec. 29,V 1931. A, R. THOKE ET AL 1,838,719

STEAMTIiAP Y Filed Nov. 17, 1928 A operating valve mechanism Patented Dec. 29, 1931 Unirse `s'rirres PATENT oFFlcE.

ALBERT R. THOKE-AND WILLIALM FRANCIS,` O1? PITTSBURGH, PENNSYLVANIA STEAM TRAP l.Application filled November 17,1928.. SerialNo.4320 ,()83.` j'

Our invention relates to steam traps, and more particularlyl to certain improvements therein for automatically removing water of condensation from steam distributing sys `tems withoutwaste of steam or in any way retarding its free flow through suchsysteni. An object of our invention is to provide means `for maintaining a float in alignment f, with a valve mechanism sctliat a more positive operation of the valve will result without binding. i z i Another object of our invention is to provide a float for operating a valve mechanism V ,j which will be free from bobbing and swaying,

caused by surging of the Ysteam* and Vwater entering the trap. A

Another ob ect of our invention is to make provision for amore positively and eiiiciently for controlling the discharge of the trap, whereby a flash of the trap will be eliminated. j

Still another object is to provide a novel' mea-ns for connecting'a valve stem with valveoper'at-ing i mechanism.

A still Ifurther object of our invention is to simplify and improve generally-the struc ture and operation of 'steam traps.,V

In the accompanying drawings,

showing it in the discharge position; Fig; 2

vis asectional view of the upper portion of the trap containing the valve mechanism' and illustratedinits closed position; Fig. 3 is a fragmentary sideview, partly in section, of the trap, and Fig. 4 1s a cross section takenV on the line IV-IV of Fig. 1. i

Referring to the drawings, the trap comprises a casing 1 which is normally closed by a cap or cover 2, which issecurely bolted to the'casingA 1, and provided with packing to" make a steam and liquid tight joint.

The bottom of the casing 1 is provided withY an inlet 3, and the cap 2 is provided with an outlet 4. The water of condensation enters the trap throughthe inletv 3 and is discharged through the outlet 4. Y

A. valve body creasing 5 is threaded into the lower end of the outlet 4,and'is provided with a valve chamber 6.3 A valve seat Z is threaded into the upper partof Vthe casing 5,

Y and Y reducing y sticking.

Figure 1 is a central vertical section through the trap,

which project downwardly a central aperture in thevalve seat providing apassageway from the chamber 7'to the outlet 4 for the discharge of water; i

guide sleeve 8 is threadedV into the lower partof the casing- 5, in alignment with the valve seat 7. A double valve 9. having a valve` l stem 10 is positioned centrally Vin the valve chamber 6 with the stem 10 projecting downwardly throughV an opening in thevv guide 4 sleeve 8. The stem 10, vfor a distance greater than the length of the guide sleeve 8, is triangular in cross section, in orderl tha-tit may freely'slide in the 'guide sleeve. Y Y

This construction involve-s ribs or radial projections from the valve stem, which make a line Contact, instead of the usual surface contact, between the stem 10'and the guide' 8,v thereby reducing friction therebetween, thepossibility of the valve posed in right angle relationto the slot'14,

extending from one edge of the link inwardly, to accommodate the upper reduced portion 11 of the stem 10.. The link 12 is posi# tioned von the stem 10,`then the link 13 is super-imposed thereon, with holes in eachleg of the links coinciding. By meansof a pin 16 extending' through theV legs Aofthe links,

the 'valve stem is thus securelyconnected to the lever17. Y

One end-of the lever 17 is pivoted to an arm 18, projecting downwardly. from the .casing 5, the other end being connected to a Vlink 19 that Vis'connectedto. a lever 20.' The lever 2O is pivotedto 'an arm 21, projecting downwardly from'the casing 5, the other en of the lever 20 being connected to links 22 andare pivotally connected to a rod 23. y

The rod 23 supportsa float or bucket-24 which is open at 'its/top. The float is adaptim ed tooperate the valve through the lever mechanism, to permit discharge of the trap.

The arm 1S is provided with a bifurcated lug 30 to which one end of an arcuate bimetallic member 31 is suitably secured. The free end of the member 3l is positioned to engage the lower edge of a pin 32 projecting outward from the pivoted end of the lever 17.

When the temperature of the trap is substantially low, the bi-metallic member 3l contracts to engage the pin 32 to maintain the valve 9 open against the flotation of the bucket 24.

Any air in the trap and steam system will be discharged through the valve opening to put the trap in proper condition to operate automatically. When steam enters the trap, the temperature of the trap rises and the lower end of the member 3l moves downwardly to release the pin 32, thereby permitting the float 24 to operate, through the lever mechanism, to close the valve 9. The member 31 is maintained in itsA expanded position, as shown in the broken lines of F ig. 3, by the high temperature ot the trap due to the presence Vof steam and water of condensation.

Normally, the valve 9, controlling the discharge passage, is maintained in its closed position by the flotation of the bucket 24. As the trap l is being filled with water of condensation, the level rises to the open top of the bucket, to iill the bucket and cause it to sink. The surging and churning water tends to cause the float to bob and swing about in the float chamber l. Such uncontrolled movements of thefloat result in excessive wear upon the associated mechanism, and may, in time, cause serious damage to the working parts of the trap, and prevent the proper operation thereof.

In order to overcome this diiiiculty, I extend the ends of the rod 23 through the sides of the bucket into vertical slots 25, for slidable engagement therewith. The slots 25 extend from the top edge of the casing l downwardly, a distance suiiicient to permit movement of the float to its lowest position.

By this construction, we restrict surging movements of the float and permit only the necessary vertical movement, andthe float is maintained in alignment with the valve mechanism thus assuring positive operation thereof.

A pipe 26 extends nearly to the bottom of the bucket 24 and has its upper end screwed into a boss 27 that projects downwardly from the casing 5.` The boss 27 is provided with apassageway 28 opening into the valve chamber 6. Vater is conducted through the pipe V2", and the passageway 28 into the chamber 6, duringvdischarge of the trap.

As previously described, the valve chamber 6 is provided with a` double Vvalve 9 comprising an upper valve disc 9a and a lower valve disc 96. The valve disc 9a engages the valve seat 7 and controls the discharge oit the trap, and the valve disc 9b engages a valve seat provided in the upper end of the guide sleeve S, to prevent steam from escaping through the opening in the guide sleeve.

rEhe inlet 3 of the trap being connected by suitable pipe connections to a steam line (not shown), the operation of our trap is as follows: 'l he water of condensation and air enter the casing 1 through the inlet 3. The air will escape through the discharge passage el as before described. rlhe inilow causes the water to rise in the casing until the buoyaney ci the water, acting upon the outer snrface of 'he bucket, causes the bucket to l until the valve 9e is seated upon the vale seat 7 to close the discharge outlet 2). The bucket is maintained in a stationaryv position while the water rises in the casing l to a level where it will pour over the upper edge and into the bucket 2-l. l/Vhen sui'licient water collects in the bucket, to overcome the flotation, the bucket will sink in the water contained in the casing l. The bucket is accelerated in its downward movement by the sudden iniiux of water, thereby imparting a positive movement to the valve-operating mechanism to open the valve 9a. The downward movement of the bucket is arrested by the closure of the valve 9b, thereby preventing Vescape oi? steam through the guide sleeve 8 (F ig. l).

The steam pressure in the casing l will force the water from the bucket 24- through the pipe 26, and through the passageway 2S into the valve chamber 6. From the chamber 6, the water passes through the valve opening and discharges through the outlet ll, which may be suitably piped to a receptacle for receiving the discharged water.

TWhen suiiicient water has been expelled from the bucket 24, it will again float, and the upward movement causes the valve Ja to close, thereby restoring the trap to a condition for a repetition et the operation just described.

lt will be noten that all the water will not be discharged irom the valve chamber with each discharge operation, before the flotation ot' the bucket causes the closure ot the discharge valve. F or a slight interval of time before the discharge valve 9a closes, each valve 9a and 9?) will be unseated. During this time however, the superincumbent pressure in the casing l will force some ot the water in the valve chamber G through the discharge opening betere the valve 9a closes. The remaining water will flow through the opening in the guide sleeve S and drop into the bucket 2&1. Due to this action, the socalled flash or escape of steam Jrrom the trap isneliminated. Also, the guide sleeve and valve stem are washed of any foreign material that may bc lodged in the guide sleeve, and that might cause sticking or improper operation oi' the valve.

The construction and operation of our trap is comparatively simple and economical,

providing for a more, continuous operation with less wear on the operating parts. Certain changes and niodiiications may be made in our trap without departingirom the scope of the appended claims.

We ciaim as our invention l. rlhe combination with a steam trap casing having an outlet passage at its upper end and a 'fioat contained therein, of a valve body connecter t said outlet and having a vaive. seat, a valve controlling flow past Vsaid seat and through the said outlet, a guideway through one wall of said valve body, a valve stem for said valve extending through said guideway, i a connection between the inner vend of saidV valve stem andthe fioat,

whereby the valve is moved to and from its seat d ring vertical movements of the float, means for preventing flow through the space between the valve stem and said guideway when the said valve is in its open position, and a thermostatic element operative to elgage said connection to maintain said valve in its open position when the trap is cold.

i2. rllhe combination with a steam trap casing having an outlet passage and a valve for,

controiling the discharge through said passage, of a Heat-actuated valve-operating mechanism having a lever, a valve stem for said valve, and a connection between the inner end of said valve stem and said valveoperating mechanism, comprising superimposed U-shaped links, positioned between shouldered end portions of said valve stem, and a pin extending through the legs of said links and said lever.V

8. The combination with a steam trap casing having an outlet passage-and a valve for controlling the discharge through said pas-x sage, of a valve-operating-mechanism havf ing a lever, a valve stem for said valve, and a connection between the inner end of said valve stem and said valve-operating mechanism, comprising a U-shaped slotted member positioned in a reduced end portion of said valve stem and aV U-shaped member having a slot in its body portion disposed at right angles to the slot in the First-named to accommodate an adjacent Vreduced end portion of said stem member, and superimposed on the l ifirst-named member, and a pin extending through the Vlegs of said members and said lever. w

ll. A steam trap comprising a casingV hav- 5. A steam trap comprising a casing having an outlet passage at its upper end, a valve for controlling the discharge through said passage, a rod in said casing having its ends extending into vertically-elongated guide slotsat diametrically opposite sides ofsaid casing, a vertically-movable bucket-float secured to said rod and depending downwardly therefrom, and lever mechanism operatively connecting said valve to said ioat.

6. A steam trap comprising a casing having an outlet passage at its upper end, a valve for controlling the discharge through said passage, aV rod in said casing having its ends Y ing diametrically opposed vertically elon-Av Y v gated slots in the side walls thereof, a rod in said casing having its endseXtending-into said slots, a vertically movable iioat suspended from said rod an outlet valve and lever mechanism operatively connecting said valve F to said float. 

